1816. I have already adverted to inertia as the continuous antagonist of solar attraction in the case of revolving planets.
1817. Agreeably to Mossotti, the creation consists of two kinds of matter, of which the homogeneous particles are mutually repellent, the heterogeneous mutually attractive. Consistently with this hypothesis, per se, any matter must be imponderable; being endowed with a property the very opposite of attraction of gravitation. This last-mentioned property exists between masses consisting of both kinds of particles, so far as the attraction between the heterogeneous atoms predominates over the repulsion between those which are homogeneous. It would follow from these premises, that all matter is ponderable or otherwise, accordingly as it may be situated.
1818. Can the ether by which, according to the undulatory theory, light is transmitted, consist of ponderable matter? Were it so, would it not be attracted about the planets with forces proportioned to their weight, respectively? and becoming of unequal density, would not the diversity in its density, thus arising, affect its undulations, as the transmission of sound is influenced by any variations in the density of the aeriform fluid by which it is propagated?
With esteem, I am yours truly,
Robert Hare
(See appendix for Whewell’s Essay.)
Additional Remarks on the Speculations of Farraday and Exley, above noticed.
1819. Is it possible for a mere centre to be endowed with a force? or reasonable that language should not make a distinction between something and nothing, between cause and effect, between matter and the properties of matter? m being the properties, and a the Newtonian atom, of which they have been considered as the attributes, I cannot concur in the reasoning which infers that where we can only perceive phenomena, we are to dispense with the idea of causation, because that causation is not directly perceptible. It seems to me, from the meaning of the words, that no cause can exist without some effect, nor can any effect exist without a cause. Language founded on the existence of ideas cannot be disused. Can there be any reason for considering any thing as endowed with existence which gives no evidence of existence? We distinguish between the thing which causes and the effect which it produces. The cause evidently has a centrality; the effect, though it indicates by the direction in which it arrives, the centre whence it proceeds, is remote from that centre. The existence of this centrality seems to be recognised in the suggestion that atoms are centres of forces. This implies that the source or cause is at the centre in each atom, and, of course, the phenomenon, being more or less remote from the centre, cannot be the source or cause, and hence has been treated as an effect or property.
1820. The suggestion that the office of atoms may be performed by centres of forces, in fact, assigns to a mere centre the part now performed by a Newtonian atom. But it must be evident that the centre is that point within any rotating mass, which does not turn therewith; and which, where neither of the opposite motions resulting from rotation take place, can neither have length nor breadth. This reduces the idea of a centre to a common definition with a mathematical point; which is nihility in the extreme. An absolutely void space may be identified with nihility, and a mathematical point is a portion of that space, without length, breadth, or thickness. To endow centres with forces is to disregard the axiom, “Out of nothing nothing can come.” Moreover, wherefore should there be a force at certain mathematical points, and yet others be destitute of the same attribute? Manifestly, if some mathematical points are deficient of powers with which others are endowed, there must be something associated with one, which is not associated with the other. This justifies the Newtonian idea, that the force, though proceeding from the centre, is, like the terrestrial attraction of gravitation, the resultant of the complicated attraction of the whole of a body surrounding the centre. But the centrality of the force does not seem to accord with the idea of the inferred diffusion of properties. In the instance of gravitation it does not account for those attributes by which this globe acts as a solid mass within its material superficies, and yet, according to the Farradian definition, reaches beyond the moon!
1821. But the idea of that polarity, of which Farraday has done so much to establish the existence in all matter, in one form or another, seems to involve that, to constitute atoms, there must be two centres of analogous, but opposite, forces in each: whence it ensues that crystals shoot in prisms or spiculæ, as water is seen to shoot in freezing; and through which salts, as deposited by the evaporation of the solvent from a solution of them, are seen to travel over the sides of the vessel; and upon which property the phenomena of electricity and magnetism appear to be dependent. How is this to be reconciled with this notion of each atom existing in a diffusible penetrable state throughout the space in which its properties prevail? Since these opposite polarities are energetic in their reciprocal polar attraction, what keeps them together, yet prevents them from so uniting as to produce neutralization?